Ferris-Wheel Type Vacuum Packaging System And Method

ABSTRACT

A vacuum packaging system for vacuumizing and sealing unsealed packages including a plurality of vacuum chambers each linked with a respective platen assembly having a platen and conveyor, each chamber and assembly arranged to receive an unsealed package and perform a vacuum sealing operation on the package, characterized by a) a conveyor apparatus including an in-feed conveyor to load each platen conveyor with an unsealed package, and an out-feed conveyor to unload each vacuumized, sealed package from each platen conveyor; and b) a ferris wheel-type vacuum packaging apparatus including at least three radially arranged vacuum chambers each linked with a respective platen assembly, each chamber and platen assembly rotatable about a central horizontal axis disposed parallel to the linear path of the conveyor apparatus, the ferris wheel-type apparatus operable in a vertical plane of rotation disposed perpendicular to the linear path of the conveyor apparatus.

FIELD OF THE INVENTION

The present invention relates to a ferris wheel-type vacuum packaging system and method.

BACKGROUND OF THE INVENTION

Vacuum packaging in heat sealable plastic bags is a conventional way of packaging food products such as meat and cheese, and involves placing the food item in a bag having a bag mouth, and then evacuating air from the bag through the bag mouth and collapsing the bag about the contained food product. The bag is then heat sealed in its evacuated condition so the food product becomes encased in a generally air-free environment. Often the bag is heat shrinkable, and after the heat sealing step, is advanced to a hot water or hot air shrink tunnel to induce shrinkage of the bag around the food product.

Vacuum packaging machines of a known type include a vacuum chamber arranged to receive an unsealed loaded bag and operable to perform a vacuum sealing operation on the loaded bag. After loading and closing the vacuum chamber, the vacuum sealing operation typically includes vacuumization, sealing the mouth of the vacuumized bag, and reintroducing air into the chamber. The chamber is then opened and the vacuum chamber is unloaded. Sometimes, the resulting package may then be conveyed to a heat-shrinking unit, typically a hot water tunnel or a dip tank, to shrink the bag around the product.

In some conventional conveyorized chamber systems, the vacuumization step typically takes at least 20 to 30 seconds. During this time, the only step which can be taken is to prepare the next packages for loading into the vacuum chamber, for example by conveying them onto an in-feed conveyor. Accordingly, the vacuum packaging machine may cause a bottle-neck in the overall packaging process.

Rotary vacuum packaging machines are known, which include a series of vacuum chambers and chain driven product platens. In operation, the platens move from a loading position, thorough a vacuum/sealing/venting stage, to an unloading position, and finally back to the loading position. One disadvantage of these machines is that they have a large footprint, and therefore take up a large amount of floor space. A further problem is that these machines generally require manual loading and bag spreading and are thus difficult to incorporate in a fully automated process. In addition, by its very nature the rotary system is not an in-line process. Typically, an unsealed package is loaded in-line, but unloaded as a vacuumized, sealed package at a right angle to the in-feed direction. This often disrupts a “streamlined” product flow through the packing area.

SUMMARY OF THE INVENTION

In a first aspect, a vacuum packaging system for vacuumizing and sealing a plurality of unsealed packages comprises a plurality of vacuum chambers each linked with a respective platen assembly, each platen assembly comprising a platen and a platen conveyor, and each vacuum chamber and platen assembly arranged to receive an unsealed package and operable to perform a vacuum sealing operation on the unsealed package, characterized in that the vacuum packaging system comprises:

-   -   a) a conveyor apparatus configured to unload a vacuumized,         sealed package from each platen conveyor, and to load an         unsealed package onto each platen conveyor, in a linear path,         the conveyor apparatus comprising         -   i) an in-feed conveyor operable to load each platen conveyor             with an unsealed package, and         -   ii) an out-feed conveyor, disposed downstream of and             longitudinally spaced apart from the in-feed conveyor,             operable to unload each vacuumized, sealed package from each             platen conveyor; and     -   b) a ferris wheel-type vacuum packaging apparatus comprising at         least three radially arranged vacuum chambers each linked with a         respective platen assembly, each chamber and platen assembly         rotatable about a central horizontal axis disposed parallel to         the linear path of the conveyor apparatus, the ferris wheel-type         vacuum packaging apparatus operable in a vertical plane of         rotation disposed perpendicular to the linear path of the         conveyor apparatus.

In a second aspect, a method of vacuumizing and sealing a plurality of unsealed packages comprises providing a plurality of vacuum chambers each linked with a respective platen assembly, each platen assembly comprising a platen and a platen conveyor, each vacuum chamber and platen assembly arranged to receive an unsealed package and operable to perform a vacuumizing and sealing operation on the unsealed package, characterized in that the method of vacuumizing and sealing a plurality of unsealed packages comprises

-   -   a) providing a conveyor apparatus configured to unload a         vacuumized, sealed package from each platen conveyor, and to         load an unsealed package onto each platen conveyor, in a linear         path, the conveyor apparatus comprising         -   i) an in-feed conveyor operable to load each platen conveyor             with an unsealed package, and         -   iii) an out-feed conveyor, disposed downstream of and spaced             apart from the in-feed conveyor, operable to unload each             vacuumized, sealed package from each platen conveyor;     -   b) providing a ferris wheel-type vacuum packaging apparatus         comprising at least three radially arranged vacuum chambers each         linked with a respective platen assembly, each chamber and         platen assembly rotatable about a central horizontal axis         disposed parallel to the linear path of the conveyor apparatus,         the ferris wheel-type vacuum packaging apparatus operable in a         vertical plane of rotation disposed perpendicular to the linear         path of the conveyor apparatus;     -   c) sequentially placing each of the plurality of unsealed         packages onto the in-feed conveyor;     -   d) advancing each unsealed package onto a platen conveyor;     -   e) closing a vacuum chamber onto the platen conveyor;     -   f) rotating the vacuum chamber and platen assembly about the         central horizontal axis, while vacuumizing and sealing the         package to produce a vacuumized, sealed package; and     -   g) unloading the vacuumized, sealed package from the platen         conveyor onto the out-feed conveyor.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described with reference to the accompanying figures, in which:

FIG. 1 is a front perspective view of the ferris wheel-type vacuum packaging system at one stage in the packaging sequence;

FIG. 2 is a view of the system of FIG. 1 at another stage in the packaging sequence;

FIG. 3 is a view of the system of FIG. 2 at another stage in the packaging sequence;

FIG. 4 is a view of the system of FIG. 3 at another stage in the packaging sequence;

FIG. 5 is a view of the system of FIG. 4 at another stage in the packaging sequence;

FIG. 6 is a view of the system of FIG. 5 at another stage in the packaging sequence;

FIG. 7 is a front perspective view of a portion of the system at one stage in a demonstration packaging sequence, showing an arrangement for advancing a vacuum chamber and platen in the ferris wheel configuration;

FIG. 8 is a view of the system of FIG. 7 at another stage in the packaging sequence;

FIG. 9 is a view of the system of FIG. 8 at another stage in the packaging sequence;

FIG. 10 is a view of the system of FIG. 9 at another stage in the packaging sequence;

FIG. 11 is a rear perspective view of the ferris wheel-type vacuum packaging system at one stage in the packaging sequence;

FIG. 12 is a view of the system of FIG. 11 at another stage in the packaging sequence;

FIG. 13 is a view of the system of FIG. 12 at another stage in the packaging sequence;

FIG. 14 is a view of the system of FIG. 13 at another stage in the packaging sequence;

FIG. 15 is a rear perspective view of a portion of the system at one stage in the packaging sequence, showing a platen-stabilizing device for maintaining a substantially horizontal orientation of each platen in the ferris wheel configuration;

FIG. 16 is a view of the system of FIG. 15 at another stage in the packaging sequence;

FIG. 17 is a view of the system of FIG. 16 at another stage in the packaging sequence;

FIG. 18 is a view of the system of FIG. 17 at another stage in the packaging sequence;

FIG. 19 is a rear perspective view of a portion of the system at one stage in the packaging sequence, showing an alternative platen-stabilizing device for maintaining a substantially horizontal orientation of each platen in the ferris wheel configuration;

FIG. 20 is a view of the system of FIG. 19 at another stage in the packaging sequence; and

FIG. 21 is a cycle chart showing representative time sequences for each major packaging function in the ferris wheel-type vacuum packaging system.

DEFINITIONS

“Ferris wheel-type” herein refers to a wheel oriented in a vertical plane, movable in a rotary manner, and having a central horizontal axis around which the wheel rotates.

“Package” herein refers to a bag or pouch, whether pre-made or made from roll-stock, that contains a product such as a meat cut or other food or non-food product.

“Unsealed package” refers to a package with one portion or mouth thereof un-sealed, such that it can be subsequently vacuumized and sealed.

DETAILED DESCRIPTION OF THE INVENTION

The system of the invention is described below, and methods of operation of the invention then follow.

FIGS. 1 to 6 show in front perspective view the ferris wheel-type vacuum packaging system 10 at various stages in the packaging sequence. In the embodiment shown in FIGS. 1 to 6, a platen-stabilizing device 151 in the form of a belt system is utilized. Conveyor apparatus 12 includes an in-feed conveyor 14, an out-feed conveyor 16, and a frame 18. Ferris wheel-type vacuum packaging apparatus 30 includes a first vacuum chamber 32 and associated first platen assembly 38, a second vacuum chamber 34 and associated second platen assembly 39, and a third vacuum chamber 36 and associated third platen assembly (not shown). Chamber 32 and platen assembly 38 are linked by first linear rail system 62. Chamber 34 and platen assembly 39 are linked by second linear rail system 64. Chamber 36 and its associated platen assembly are linked by third linear rail system 66. In the embodiments shown, ferris wheel-type apparatus 30 is shown with three vacuum chambers, each with an associated platen assembly and a linear rail system that links each chamber/platen assembly combination. Apparatus 30 can alternatively include four, five, six or more chambers, each with an associated platen assembly, linear rail system, and other components described herein that serve to enable the function of each chamber and associated platen assembly.

FIGS. 7 to 10 show in front perspective view a portion of the ferris wheel-type vacuum packaging system in a demonstration prototype at various stages in the packaging sequence, showing an arrangement for advancing a vacuum chamber and associated platen assembly. A detent support 50 extends vertically from frame 18, and is fitted with a pivotable detent 48. First platen 41 is fitted with a first platen arm 52. Second platen 43 is fitted with a second platen arm (not shown). The third platen (not shown) is fitted with a third platen arm (not shown).

FIGS. 11 to 14 show in rear perspective view the ferris wheel-type vacuum packaging apparatus 30, including a drive motor 90, located on one side of apparatus 30. The apparatus includes four slip ring assemblies. The main slip ring assembly 80 is located on the center axis of apparatus 30. The three chamber slip ring assemblies 82, 84 and 86 are mounted on the center axis of each of vacuum chambers 32, 34, and 36 respectively. Internal to a slip ring associated with each slip ring assembly is a series of circular tracks and brushes that allow continuous connection of electrical signals and power through a pivot joint that rotates 360 degrees. The vacuum chambers also require pneumatic supply, and are equipped with a pneumatic coupling that allows for 360 degree rotation. In the embodiment shown in FIGS. 11 to 14, a platen-stabilizing device 101 in the form of a parallel plate system is utilized.

On the side of apparatus 30 opposite the drive motor 90, a vacuum inlet 91 provides vacuumization to the vacuum chambers through a first valve 92, operatively connected to first vacuum chamber 32; second valve 94, operatively connected to second vacuum chamber 34; and third valve 96, operatively connected to third vacuum chamber 36. Main slip ring assembly 80 communicates with first slip ring assembly 82, second slip ring assembly 84, and third slip ring assembly 86, to provide positive air pressure and electrical power and control signals to drive the platen motor, seal wires, pneumatic valves and one or more air cylinders 162, 164 and 166 in each of vacuum chambers 32, 34, and 36 respectively, in order to operate a heat sealing assembly, including a seal bar, clamp, and cutting device disposed in each respective vacuum chamber. The heat sealing assembly within each vacuum chamber of the present invention is of a type well known in the art, e.g. as disclosed in U.S. Pat. No. 7,296,390 (Koke et al.), this patent incorporated herein by reference in its entirety.

FIGS. 15 to 18 show in rear perspective view a portion of the ferris wheel-type vacuum packaging apparatus 30 at various stages in the packaging sequence. Platen-stabilizing device 101 includes a drive plate 102 driven by central drive shaft 70, and a slave plate 103 connected to and driven by drive plate 102. Drive plate 102 includes first drive plate armature 112, second drive plate armature 114, and third drive plate armature 116. Slave plate 103 includes first slave plate armature 122, second slave plate armature 124, and third slave plate armature 126.

FIGS. 19 and 20 show in rear perspective view a portion of the ferris wheel-type vacuum packaging apparatus 30 at various stages in the packaging sequence. A first alternative platen-stabilizing device 131 includes a central gear 140 driven by central drive shaft 70. A first terminal gear 142 is shown interconnected to first vacuum chamber 32; second and third terminal gears 144 and 146 are suitably connected to second and third vacuum chambers 34 and 36 respectively (not shown in FIG. 19 or 20). Rotary motion is imparted to the three terminal gears 142, 144, and 146 by means of first intermediate gear array 143, second intermediate gear array 145, and third intermediate gear array 147 respectively.

A second alternative platen-stabilizing device 151, shown in FIGS. 1 to 6, includes a first timing belt extension 152, a second timing belt extension 154, and a third timing belt extension 156. Device 151 is in one embodiment a single belt with the extensions as shown.

Method of Operation

The vacuum packaging system 10 would typically be located downstream from a manual, semi-automatic, or fully automatic bagging machine. A fixed input conveyor or other suitable device (not shown) would deliver unsealed packages to the in-feed conveyor 14. In one embodiment, the packages are oriented such that the unsealed portion of each package is trailing.

Apparatus 12 and apparatus 30 operate in a synchronized manner. An electronic control system (not shown) such as a programmable logic controller or other suitable control system controls operation and synchronization of the different operations and functions that occur within apparatus 12 and apparatus 30 by means of suitable programming of the control system. These operations include rotationally advancing a platen assembly, having a vacuumized and sealed package on the platen conveyor thereof (previously loaded as an unsealed package onto the platen conveyor) to an unloading/loading position located between the in-feed and out-feed conveyors; unloading the vacuumized and sealed package from the platen conveyor onto the out-feed conveyor; loading (simultaneously with or subsequent to the unloading operation) an unsealed package from the in-feed conveyor onto the platen conveyor; closing a vacuum chamber onto the loaded platen conveyor; and rotationally advancing the vacuum chamber and associated platen assembly, including the loaded platen conveyor, a predetermined distance away from the unloading/loading position to a first intermediate position. The apparatus 30 pauses to allow a second unloading/loading operation, as described above, for the next vacuumized and sealed package arriving at the unloading/loading position. The entire operation occurs in intermittent cycles timed to the number of vacuum chambers and platen assemblies present in apparatus 30. For example, in an embodiment where three vacuum chambers and associated platen assemblies are present, as shown in the drawings, a first and second intermediate position are defined in the rotary cycle. As shown in FIG. 21 there are two interdependent timing cycles. The inner circle represents the load/unload and rotate cycle, the outer ring shows the chamber cycle of closing the chamber, vacuumizing, sealing, cooling and venting and opening the chamber. The two cycles are balanced, to the extent that the vacuum cycle of each chamber must be completed in the time it takes for apparatus 30 to complete one rotation. Since the vacuum system is shared between the three chambers, the speed of rotation is timed to allow three chambers to be adequately evacuated in the time it takes for apparatus 30 to rotate once. It should be noted that the arrival of each vacuum chamber and associated platen assembly to the location where package loading/unloading takes place, does not necessarily initiate the vacuumizing/sealing operation. The two operations are independent to the extent that e.g. vacuumization can start as soon as the vacuum chamber is closed onto the platen assembly, i.e. before the chamber arrives at the first intermediate location.

Thus, as shown in the embodiments of the drawings, packages can be present in one, two, or all three of the vacuum chambers 32, 34 and 36, the packages disposed on any or all of platen conveyors 42, 44 and 46 respectively. Each package is in some state ranging from an unsealed package when first loaded onto a platen, to a vacuumized and sealed package at a later stage in the rotary cycle before the package is unloaded from the platen. Thus, in a relatively small footprint, packages are in one embodiment simultaneously being loaded, vacuumized, sealed, and unloaded, and the linear downstream movement of an unsealed package, and a vacuumized and sealed package occurs in intermittent steps even while one or more packages is/are being vacuumized and sealed in apparatus 30 synchronized with the loading/unloading process. This results in reduced cycle time in a relatively small space.

In one embodiment, system 10 can optionally be operated in a mode in which, after a first unsealed package is loaded onto a first platen conveyor, the system will rotate apparatus 30, simultaneously resulting in rotational advancement of a platen assembly, having a second platen conveyor, to the loading/unloading position where any vacuumized sealed package present can be unloaded from the second platen conveyor. The system will pause in this state and will not load the second platen conveyor until a second unsealed package is disposed on the in-feed conveyor. When a suitable sensing device (not shown) indicates that condition, the unsealed package will be loaded on the second platen conveyor and apparatus 30 then resumes rotation.

In the sequence shown in FIGS. 1 to 6, the conveyor apparatus 12 operates to move packages in a linear path from right to left, and the ferris wheel-type vacuum packaging apparatus 30 operates to move packages in a rotational path in a counter-clockwise direction as viewed from the right side (drive motor 90) of the drawings. The rotational path of apparatus 30 is in a vertical plane substantially perpendicular to the linear path of the packages and conveyors of apparatus 12.

In one embodiment, vacuumized and sealed package 22 containing a meat cut is disposed on platen conveyor 44 housed in vacuum chamber 34 (see FIGS. 1 to 3). As vacuum chamber 34 and platen conveyor 44 approach an unloading/loading position located between the in-feed and out-feed conveyors 14 and 16 respectively, platen assembly 39, including platen conveyor 44 drops by gravity, the drop suitably dampened by any appropriate dampening device such as a pneumatic cylinder (not shown) until a platen arm (not shown, but see platen arm 52 in FIG. 7) catches at detent 48 (see the sequence of FIGS. 9 and 10). Platen assembly 39, including platen conveyor 44 thus temporarily separates spatially from vacuum chamber 34 (see FIGS. 3 and 4). Chamber 34 remains in this open state until the completion of the load/unload operation. When platen conveyor 44 reaches the unloading/loading position, a vacuumized and sealed package 22 is advanced from the platen conveyor onto out-feed conveyor 16 (see FIG. 4) by activating the platen conveyor, and unsealed package 24 is advanced onto now-vacated platen conveyor 44.

An optional bridging member 20 (see FIG. 4) can be used to facilitate advancing and loading an unsealed package onto a platen located at the unloading/loading position. In one embodiment, a telescoping conveyor 20 (see FIG. 4) extends from below in-feed conveyor 14 to bridge the gap between the downstream end of in-feed conveyor 14, and the platen to be loaded, so as to facilitate loading of an unsealed package onto the platen. Conveyor 20 can be an extension of in-feed conveyor 14, a discrete member, or any other component suitable to bridge the gap between the in-feed conveyor and the platen. After loading the package, conveyor 20 can be retracted.

The in-feed, out-feed, and platen conveyors are each driven by a suitable motive device such as a drum motor. Vacuumized and sealed package 22 can be manually or automatedly packed off into a shipping container or sent to another station for further processing, such as a hot water shrink tunnel. System 10 can optionally include a scrap removal device 28 to remove any cut-off portions (scrap) of packaging material located in a vacuum chamber or on a platen after a package has been vacuumized and sealed, and when the platen conveyor carrying the package has been advanced to the unloading/loading position located between the in-feed and out-feed conveyors. Device 28 can include e.g. any combination of an air curtain and/or suction, and be located at any suitable location near the unloading/loading position. The position of device 28 in FIGS. 1 to 6 is shown only for purposes of illustration.

After the unsealed package 24 is loaded on the platen conveyor 44, apparatus 30 resumes rotation and vacuum chamber 34 rejoins platen assembly 39, with platen conveyor 44 now holding another unsealed package 24. Detent 48 is moved to release platen arm 52, and thus platen assembly 39, as chamber 34 rotates and closes onto platen assembly 39. Chamber 34 remains linked to platen assembly 39 by linear rail system 64, which enables platen assembly 39 to drop temporarily from chamber 34 as described above, but ensures that subsequently in the packaging cycle, chamber 34 and platen assembly 39 resume their relative positions for purposes of vacuumization and sealing of each unsealed package. Likewise, chamber 32 remains linked to platen assembly 38 by linear rail system 62, and chamber 36 remains linked to platen assembly 40 by linear rail system 66 (see also FIGS. 11 to 14).

The vacuumization/sealing cycle then initiates and vacuum chamber 34 and associated platen assembly 39 advance rotationally to a first intermediate position. The rotational movement of chamber 34 and platen assembly 39 necessarily causes equivalent rotational movement of chamber 36 and associated platen assembly 40 (not shown). and chamber 32 and associated platen assembly 38 (not shown). When chamber 34 and platen assembly 39 reach the first intermediate position, chamber 32 and associated platen assembly 38 reach a second intermediate position, and any remaining vacuumization, sealing, and cutting is done to produce a vacuumized and sealed package on platen conveyor 42 in vacuum chamber 32. Thus, in intermittent fashion, vacuumized and sealed packages are unloaded onto out-feed conveyor 16, and unsealed packages are loaded onto a platen positioned at the unloading/loading position located between the in-feed and out-feed conveyors, synchronously with the vacuumization and sealing of unsealed packages disposed on platen conveyors advancing rotationally around the ferris wheel-type vacuum sealing system 10.

Vacuum Chamber Operation

Each vacuum chamber is equipped with a heat seal assembly (not shown). After an unsealed package has been loaded onto a platen, and as the associated vacuum chamber rejoins the platen, as the vacuum chamber moves downwardly, components of the heat seal assembly, of a type well known in the art, in one embodiment including a heat seal anvil and heat seal bar that are moved towards each other, by the relative movement of one or both of these components. The mouth of the unsealed package is compressed between the heat seal bar and anvil, such that the mouth is positioned substantially flat. Positive air pressure is used to drive one or more air cylinders in each vacuum chamber to effect movement of heat seal bars, clamps, cutting knives, etc. as described herein. A first set of air cylinders 162 is provided for vacuum chamber 32; a second set of air cylinders 164 is provided for vacuum chamber 34; and a third set of air cylinders 166 is provided for vacuum chamber 36.

Each package is vacuumized by a vacuumization process, such as those well known in the art. Vacuum inlet 91 (see FIG. 12) operates to draw vacuum, through a vacuum valve, for each chamber. The three chamber embodiment as shown includes a first valve 92 for chamber 32, a second valve 94 for chamber 34, and a third valve 96 for chamber 36. Each chamber can optionally include a puncturing device which is operable to puncture at least one aperture in the package adjacent the heat seal assembly, so that as each vacuum operation is performed, air is forced out of the package through the punctured aperture(s) prior to heat sealing. The puncturing device may comprise e.g. a plurality of piercing knives.

Once evacuated, an electrical current is applied to the heat seal bar to heat seal the package. Once sealed, the package is cut by a suitable cutting device such as a serrated knife to shear the scrap portion of the package between the heat seal and the end of the package, air is introduced back into the chamber, and the chamber is opened as described above to unload the vacuumized, sealed package, and load an unsealed package; and the packaging cycle repeats.

In one embodiment, each vacuum chamber further includes a puncturing device which is operable to puncture at least one aperture in an unsealed package adjacent the location in the package where a heat seal is to be made, such that as each vacuum sealing operation occurs, air is forced out of the package through the punctured aperture(s) prior to heat sealing. The puncturing device may comprise a plurality of piercing knives.

In one embodiment, the heat seal bar and anvil are positioned in each vacuum chamber transversely to the linear path of the conveyor apparatus, enabling each package to be loaded into each chamber with its unopened end transverse to the linear path.

Electrical power is supplied to the heat sealing assembly of each vacuum chamber through a slip ring assembly that includes a spring brush that rides on a track that provides power to each vacuum chamber.

Referring to FIG. 21, the inner circle shows vacuum chamber loading and rotating cycles for a three chamber system; the outer circle shows the full cycle of a given vacuum chamber. The other chamber cycles are rotated 120°. Shown are representative times based on 1.4 seconds rotation and 1.6 seconds product loading. Actual loading time is about 2 seconds, taking into account about 0.4 seconds for the platen to drop from its associated vacuum chamber, and subsequently reclose after loading. With each chamber's timing rotated 120 degrees a single vacuum system can be shared by the three chambers.

Platen-Stabilizing Device

To keep each platen assembly in a substantially horizontal configuration during the package cycle, the ferris wheel-type vacuum packaging apparatus can further comprise a platen-stabilizing device. This device functions to stabilize and hold each platen assembly in a horizontal plane throughout the rotation of apparatus 30. This in turn stabilizes each package during the vacuumization/ sealing operation, and provides for a smooth transition that facilitates the accurate placement of the unsealed end of each unsealed package over a respective seal bar.

In one embodiment, shown in FIGS. 15 to 18, the platen-stabilizing device 101 includes a drive plate 102 driven by central drive shaft 70 powered by drive motor 90, and a slave plate 103. The operative rotary motion of apparatus 30 is counterclockwise as viewed in FIGS. 15 to 18, and the figures are shown in regressive sequence, i.e. with FIG. 18 showing the apparatus at a first position, FIG. 17 showing the apparatus at a position somewhat advanced from the first position, etc. It can be seen that the drive plate is connected to and drives slave plate 103 by a suitable mechanism, such as internal/external gears, so that rotational movement of the drive plate causes concomitant rotational movement of the slave plate. The armatures of the drive plate are each connected in pivotable fashion to a respective vacuum chamber, and armatures on the slave plate are connected by a suitable linkage to corresponding armatures on the drive plate. More generally, the number of armatures on each of the drive and slave plates will correspond with the number of vacuum chambers present in the system.

In another embodiment, the platen-stabilizing device comprises a gear system (see FIGS. 19 and 20) with a terminal gear attached to each of the plurality of vacuum chambers.

In still another embodiment, the platen-stabilizing device 151 comprises a belt system (see FIGS. 1 to 6) comprising a single timing belt attached at extensions 152, 154, and 156 respectively to each of the plurality of vacuum chambers 32, 34 and 36.

The effect of each of these approaches is that each platen assembly remains in a substantially horizontal orientation during the packaging cycle, and additionally that the each vacuum chamber and linked platen assembly (in this embodiment, three in number) remain equally spaced radially from one another.

The present application is directed in various aspects to the subject matter described in the following paragraphs.

Aspect 1. A vacuum packaging system for vacuumizing and sealing a plurality of unsealed packages comprising a plurality of vacuum chambers each linked with a respective platen assembly, each platen assembly comprising a platen and a platen conveyor, and each vacuum chamber and platen assembly arranged to receive an unsealed package and operable to perform a vacuum sealing operation on the unsealed package, characterized in that the vacuum packaging system comprises:

-   -   a) a conveyor apparatus configured to unload a vacuumized,         sealed package from each platen conveyor, and to load an         unsealed package onto each platen conveyor, in a linear path,         the conveyor apparatus comprising         -   i) an in-feed conveyor operable to load each platen conveyor             with an unsealed package, and         -   ii) an out-feed conveyor, disposed downstream of and             longitudinally spaced apart from the in-feed conveyor,             operable to unload each vacuumized, sealed package from each             platen conveyor ; and     -   b) a ferris wheel-type vacuum packaging apparatus comprising at         least three radially arranged vacuum chambers each linked with a         respective platen assembly, each chamber and platen assembly         rotatable about a central horizontal axis disposed parallel to         the linear path of the conveyor apparatus, the ferris wheel-type         vacuum packaging apparatus operable in a vertical plane of         rotation disposed perpendicular to the linear path of the         conveyor apparatus.

Aspect 2. A method of vacuumizing and sealing a plurality of unsealed packages comprising:

-   -   a) providing a plurality of vacuum chambers each linked with a         respective platen assembly, each platen assembly comprising a         platen and a platen conveyor, each vacuum chamber and platen         assembly arranged to receive an unsealed package and operable to         perform a vacuumizing and sealing operation on the unsealed         package;     -   b) providing a conveyor apparatus configured to unload a         vacuumized, sealed package from each platen conveyor, and to         load an unsealed package onto each platen conveyor, in a linear         path, the conveyor apparatus comprising         -   i) an in-feed conveyor operable to load each platen conveyor             with an unsealed package, and         -   ii) an out-feed conveyor, disposed downstream of and spaced             apart from the in-feed conveyor, operable to unload each             vacuumized, sealed package from each platen conveyor;     -   c) providing a ferris wheel-type vacuum packaging apparatus         comprising at least three radially arranged vacuum chambers each         associated with a respective platen assembly, each chamber and         platen assembly rotatable about a central horizontal axis         disposed parallel to the linear path of the conveyor apparatus,         the ferris wheel-type vacuum packaging apparatus operable in a         vertical plane of rotation disposed perpendicular to the linear         path of the conveyor apparatus;

d) sequentially placing each of the plurality of unsealed packages onto the in-feed conveyor;

-   -   e) advancing each unsealed package onto a platen conveyor;     -   f) closing a vacuum chamber onto the platen conveyor;     -   g) rotating the vacuum chamber and platen assembly about the         central axis, while vacuumizing and sealing the package to         produce a vacuumized, sealed package; and     -   h) unloading the vacuumized, sealed package from the platen         conveyor onto the out-feed conveyor.

Aspect 3. The vacuum packaging system of any of aspects 1 or 2 wherein the conveyor apparatus further comprises a bridging member configured to facilitate downstream movement of each unsealed package onto each platen conveyor.

Aspect 4. The vacuum packaging system of any of aspects 1 to 3 wherein the bridging member comprises a telescoping conveyor operable to bridge the space between the in-feed conveyor and the platen onto which the unsealed package is loaded.

Aspect 5. The vacuum packaging system of any of aspects 1 to 4 wherein the ferris wheel-type vacuum packaging apparatus comprises three radially arranged vacuum chambers each linked with a respective platen assembly.

Aspect 6. The vacuum packaging system any of aspects 1 to 5 wherein a heat seal assembly is associated with each vacuum chamber and linked platen assembly.

Aspect 7. The vacuum packaging system of any of aspects 1 to 6 wherein the ferris wheel-type vacuum packaging apparatus comprises a first side and a second side, with a drive device for driving the apparatus disposed on the first side, and a vacuum inlet for vacuumizing each unsealed package loaded on a respective platen conveyor disposed on the second side.

Aspect 8. The vacuum packaging system of any of aspects 1 to 7 wherein each vacuum chamber and linked platen assembly are linked with a linear rail system operable to effect relative movement between the chamber and platen assembly.

Aspect 9. The vacuum packaging system of any of aspects 1 to 8 wherein each of the conveyor apparatus and ferris wheel-type vacuum packaging apparatus are configured to move in a pre-determined intermittent manner.

Aspect 10. The vacuum packaging system of any of aspects 1 to 9 wherein the ferris wheel-type vacuum packaging apparatus further comprises a platen-stabilizing apparatus.

Aspect 11. The vacuum packaging system of any of aspects 1 to 10 wherein the platen-stabilizing apparatus comprises a drive plate connected to a slave plate, both plates attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.

Aspect 12. The vacuum packaging system of any of aspects 1 to 11 wherein the platen-stabilizing apparatus comprises a gear system attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.

Aspect 13. The vacuum packaging system of any of aspects 1 to 12 wherein the platen-stabilizing apparatus comprises a belt system comprising a single belt attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.

Aspect 14. The vacuum packaging system of any of aspects 1 to 13 wherein the ferris wheel-type vacuum packaging apparatus further comprises a vacuum system comprising a central vacuum inlet in communication with a plurality of vacuum valves operative to provide vacuumization of an unsealed package in each of the vacuum chambers.

Aspect 15. The vacuum packaging system of any of aspects 1 to 14 wherein the ferris wheel-type vacuum packaging apparatus further comprises a slip ring system operative to convey electrical signals and power and air pressure to control each of the vacuum chambers to effect predetermined movement of a heat sealing assembly, a cut-off knife, and a piercing knife, and to drive each of the platen conveyors and provide electrical current to seal wires disposed in each of the vacuum chambers to provide sealing of an unsealed package in each of the vacuum chambers.

Aspect 16. The vacuum packaging system of any of aspects 1 to 15 wherein the ferris wheel-type vacuum packaging apparatus further comprises a device for providing controlled descent of a platen assembly, then temporarily stopping the platen assembly, and then advancing the platen assembly, during the packaging cycle.

Aspect 17. The vacuum packaging system of any of aspects 1 to 16 wherein the conveyor apparatus is operable to simultaneously unload a vacuumized, sealed package from a platen conveyor, and load an unsealed package onto the platen conveyor.

Aspect 18. The vacuum packaging system of any of aspects 1 to 17 wherein the ferris wheel-type vacuum packaging apparatus is configured to perform at least part of a vacuum sealing operation in one of the plurality of vacuum chambers while loading an unsealed package on a platen conveyor linked with another of the plurality of vacuum chambers.

Aspect 19. The vacuum packaging system of any of aspects 1 to 18 wherein each unsealed package can be loaded onto a platen conveyor with an unopened end of the package oriented transversely to the linear path of the conveyor apparatus.

Aspect 20. The vacuum packaging system of any of aspects 1 to 19 wherein the in-feed conveyor is configured to load an unsealed package onto a platen conveyor with an unsealed portion of the package trailing.

It will be understood that the configuration, construction, size, function and operation of each of the first, second, and third vacuum chambers and components thereof, and each of the first, second, and third platen assemblies and components thereof, as described herein, will typically be the same or similar. 

What is claimed is:
 1. A vacuum packaging system for vacuumizing and sealing a plurality of unsealed packages comprising a plurality of vacuum chambers each linked with a respective platen assembly, each platen assembly comprising a platen and a platen conveyor, and each vacuum chamber and platen assembly arranged to receive an unsealed package and operable to perform a vacuum sealing operation on the unsealed package, characterized in that the vacuum packaging system comprises: a) a conveyor apparatus configured to unload a vacuumized, sealed package from each platen conveyor, and to load an unsealed package onto each platen conveyor, in a linear path, the conveyor apparatus comprising i) an in-feed conveyor operable to load each platen conveyor with an unsealed package, and ii) an out-feed conveyor, disposed downstream of and longitudinally spaced apart from the in-feed conveyor, operable to unload each vacuumized, sealed package from each platen conveyor; and b) a ferris wheel-type vacuum packaging apparatus comprising at least three radially arranged vacuum chambers each linked with a respective platen assembly, each chamber and platen assembly rotatable about a central horizontal axis disposed parallel to the linear path of the conveyor apparatus, the ferris wheel-type vacuum packaging apparatus operable in a vertical plane of rotation disposed perpendicular to the linear path of the conveyor apparatus.
 2. The vacuum packaging system of claim 1 wherein the conveyor apparatus further comprises a bridging member configured to facilitate downstream movement of each unsealed package onto each platen conveyor.
 3. The vacuum packaging system of claim 2 wherein the bridging member comprises a telescoping conveyor operable to bridge the space between the in-feed conveyor and the platen onto which the unsealed package is loaded.
 4. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus comprises three radially arranged vacuum chambers each linked with a respective platen assembly.
 5. The vacuum packaging system as claimed in claim 1 wherein a heat seal assembly is associated with each vacuum chamber and linked platen assembly.
 6. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus comprises a first side and a second side, with a drive device for driving the apparatus disposed on the first side, and a vacuum inlet for vacuumizing each unsealed package loaded on a respective platen conveyor disposed on the second side.
 7. The vacuum packaging system of claim 1 wherein each vacuum chamber and linked platen assembly are linked with a linear rail system operable to effect relative movement between the chamber and platen assembly.
 8. The vacuum packaging system of claim 1 wherein each of the conveyor apparatus and ferris wheel-type vacuum packaging apparatus are configured to move in a predetermined intermittent manner.
 9. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus further comprises a platen-stabilizing apparatus.
 10. The vacuum packaging system of claim 9 wherein the platen-stabilizing apparatus comprises a drive plate connected to a slave plate, both plates attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.
 11. The vacuum packaging system of claim 9 wherein the platen-stabilizing apparatus comprises a gear system attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.
 12. The vacuum packaging system of claim 9 wherein the platen-stabilizing apparatus comprises a belt system comprising a single belt attached to each of the plurality of vacuum chambers such that each platen assembly is in a substantially horizontal orientation during the packaging cycle.
 13. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus further comprises a vacuum system comprising a central vacuum inlet in communication with a plurality of vacuum valves operative to provide vacuumization of an unsealed package in each of the vacuum chambers.
 14. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus further comprises a slip ring system operative to convey electrical signals and power and air pressure to control each of the vacuum chambers to effect predetermined movement of a heat sealing assembly, a cut-off knife, and a piercing knife, and to drive each of the platen conveyors and provide electrical current to seal wires disposed in each of the vacuum chambers to provide sealing of an unsealed package in each of the vacuum chambers.
 15. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus further comprises a device for providing controlled descent of a platen assembly, then temporarily stopping the platen assembly, and then advancing the platen assembly, during the packaging cycle.
 16. The vacuum packaging system of claim 1 wherein the conveyor apparatus is operable to simultaneously unload a vacuumized, sealed package from a platen conveyor, and load an unsealed package onto the platen conveyor.
 17. The vacuum packaging system of claim 1 wherein the ferris wheel-type vacuum packaging apparatus is configured to perform at least part of a vacuum sealing operation in one of the plurality of vacuum chambers while loading an unsealed package on a platen conveyor linked with another of the plurality of vacuum chambers.
 18. The vacuum packaging system of claim 1 wherein each unsealed package can be loaded onto a platen conveyor with an unopened end of the package oriented transversely to the linear path of the conveyor apparatus.
 19. The vacuum packaging system of claim 1 wherein the in-feed conveyor is configured to load an unsealed package onto a platen conveyor with an unsealed portion of the package trailing.
 20. A method of vacuumizing and sealing a plurality of unsealed packages comprising: a) providing a plurality of vacuum chambers each linked with a respective platen assembly, each platen assembly comprising a platen and a platen conveyor, each vacuum chamber and platen assembly arranged to receive an unsealed package and operable to perform a vacuumizing and sealing operation on the unsealed package; b) providing a conveyor apparatus configured to unload a vacuumized, sealed package from each platen conveyor, and to load an unsealed package onto each platen conveyor, in a linear path, the conveyor apparatus comprising i) an in-feed conveyor operable to load each platen conveyor with an unsealed package, and ii) an out-feed conveyor, disposed downstream of and spaced apart from the in-feed conveyor, operable to unload each vacuumized, sealed package from each platen conveyor; c) providing a ferris wheel-type vacuum packaging apparatus comprising at least three radially arranged vacuum chambers each associated with a respective platen assembly, each chamber and platen assembly rotatable about a central horizontal axis disposed parallel to the linear path of the conveyor apparatus, the ferris wheel-type vacuum packaging apparatus operable in a vertical plane of rotation disposed perpendicular to the linear path of the conveyor apparatus; d) sequentially placing each of the plurality of unsealed packages onto the in-feed conveyor; e) advancing each unsealed package onto a platen conveyor; f) closing a vacuum chamber onto the platen conveyor; g) rotating the vacuum chamber and platen assembly about the central axis, while vacuumizing and sealing the package to produce a vacuumized, sealed package; and h) unloading the vacuumized, sealed package from the platen conveyor onto the out-feed conveyor. 